<?php

/**
 * @file
 * User page callbacks for the book module.
 */

/**
 * Menu callback; prints a listing of all books.
 */
function book_render() {
	$book_list = array();
	foreach (book_get_books() as $book) {
		$book_list[] = l($book['title'], $book['href'], $book['options']);
	}

	return theme('item_list', array('items' => $book_list));
}

/**
 * Menu callback; Generates various representation of a book page and its children.
 *
 * The function delegates the generation of output to helper functions.
 * The function name is derived by prepending 'book_export_' to the
 * given output type. So, e.g., a type of 'html' results in a call to
 * the function book_export_html().
 *
 * @param $type
 *   A string encoding the type of output requested. The following
 *   types are currently supported in book module:
 *
 *   - html: HTML (printer friendly output)
 *
 *   Other types may be supported in contributed modules.
 * @param $nid
 *   An integer representing the node id (nid) of the node to export
 * @return
 *   A string representing the node and its children in the book hierarchy
 *   in a format determined by the $type parameter.
 */
function book_export($type, $nid) {
	$type = drupal_strtolower($type);

	$export_function = 'book_export_' . $type;

	if (function_exists($export_function)) {
		print call_user_func($export_function, $nid);
	}
	else {
		drupal_set_message(t('Unknown export format.'));
		drupal_not_found();
	}
}

/**
 * This function is called by book_export() to generate HTML for export.
 *
 * The given node is /embedded to its absolute depth in a top level
 * section/. For example, a child node with depth 2 in the hierarchy
 * is contained in (otherwise empty) &lt;div&gt; elements
 * corresponding to depth 0 and depth 1. This is intended to support
 * WYSIWYG output - e.g., level 3 sections always look like level 3
 * sections, no matter their depth relative to the node selected to be
 * exported as printer-friendly HTML.
 *
 * @param $nid
 *   An integer representing the node id (nid) of the node to export.
 * @return
 *   A string containing HTML representing the node and its children in
 *   the book hierarchy.
 */
function book_export_html($nid) {
	if (user_access('access printer-friendly version')) {
		$export_data = array();
		$node = node_load($nid);
		if (isset($node->book)) {
			$tree = book_menu_subtree_data($node->book);
			$contents = book_export_traverse($tree, 'book_node_export');
			return theme('book_export_html', array('title' => $node->title, 'contents' => $contents, 'depth' => $node->book['depth']));
		}
		else {
			drupal_not_found();
		}
	}
	else {
		drupal_access_denied();
	}
}

/**
 * Menu callback; show the outline form for a single node.
 */
function book_outline($node) {
	drupal_set_title($node->title);
	return drupal_get_form('book_outline_form', $node);
}

/**
 * Build the form to handle all book outline operations via the outline tab.
 *
 * @see book_outline_form_submit()
 * @see book_remove_button_submit()
 *
 * @ingroup forms
 */
function book_outline_form($form, &$form_state, $node) {
	if (!isset($node->book)) {
		// The node is not part of any book yet - set default options.
		$node->book = _book_link_defaults($node->nid);
	}
	else {
		$node->book['original_bid'] = $node->book['bid'];
	}

	// Find the depth limit for the parent select.
	if (!isset($node->book['parent_depth_limit'])) {
		$node->book['parent_depth_limit'] = _book_parent_depth_limit($node->book);
	}
	$form['#node'] = $node;
	$form['#id'] = 'book-outline';
	_book_add_form_elements($form, $form_state, $node);

	$form['book']['#collapsible'] = FALSE;

	$form['update'] = array(
			'#type' => 'submit',
			'#value' => $node->book['original_bid'] ? t('Update book outline') : t('Add to book outline'),
			'#weight' => 15,
	);

	$form['remove'] = array(
			'#type' => 'submit',
			'#value' => t('Remove from book outline'),
			'#access' => $node->nid != $node->book['bid'] && $node->book['bid'],
			'#weight' => 20,
			'#submit' => array('book_remove_button_submit'),
	);

	return $form;
}

/**
 * Button submit function to redirect to removal confirm form.
 *
 * @see book_outline_form()
 */
function book_remove_button_submit($form, &$form_state) {
	$form_state['redirect'] = 'node/' . $form['#node']->nid . '/outline/remove';
}

/**
 * Handles book outline form submissions from the outline tab.
 *
 * @see book_outline_form()
 */
function book_outline_form_submit($form, &$form_state) {
	$node = $form['#node'];
	$form_state['redirect'] = "node/" . $node->nid;
	$book_link = $form_state['values']['book'];
	if (!$book_link['bid']) {
		drupal_set_message(t('No changes were made'));

		return;
	}

	$book_link['menu_name'] = book_menu_name($book_link['bid']);
	$node->book = $book_link;
	if (_book_update_outline($node)) {
		if ($node->book['parent_mismatch']) {
			// This will usually only happen when JS is disabled.
			drupal_set_message(t('The post has been added to the selected book. You may now position it relative to other pages.'));
			$form_state['redirect'] = "node/" . $node->nid . "/outline";
		}
		else {
			drupal_set_message(t('The book outline has been updated.'));
		}
	}
	else {
		drupal_set_message(t('There was an error adding the post to the book.'), 'error');
	}
}

/**
 * Menu callback; builds a form to confirm removal of a node from the book.
 *
 * @see book_remove_form_submit()
 *
 * @ingroup forms
 */
function book_remove_form($form, &$form_state, $node) {
	$form['#node'] = $node;
	$title = array('%title' => $node->title);

	if ($node->book['has_children']) {
		$description = t('%title has associated child pages, which will be relocated automatically to maintain their connection to the book. To recreate the hierarchy (as it was before removing this page), %title may be added again using the Outline tab, and each of its former child pages will need to be relocated manually.', $title);
	}
	else {
		$description = t('%title may be added to hierarchy again using the Outline tab.', $title);
	}

	return confirm_form($form, t('Are you sure you want to remove %title from the book hierarchy?', $title), 'node/' . $node->nid, $description, t('Remove'));
}

/**
 * Confirm form submit function to remove a node from the book.
 *
 * @see book_remove_form()
 */
function book_remove_form_submit($form, &$form_state) {
	$node = $form['#node'];
	if ($node->nid != $node->book['bid']) {
		// Only allowed when this is not a book (top-level page).
		menu_link_delete($node->book['mlid']);
		db_delete('book')
		->condition('nid', $node->nid)
		->execute();
		drupal_set_message(t('The post has been removed from the book.'));
	}
	$form_state['redirect'] = 'node/' . $node->nid;
}
